The present invention pertains to a motorcycle mirror mount that automatically adjusts the rear view mirrors of a motorcycle to present substantially the same view during tilting and turning of the motorcycle as during straight riding, regardless of the degree and direction of tilt or turn of the motorcycle.
Unlike automobiles and other vehicles that ride on three or more wheels, two-wheeled motorcycles, motorscooters and the like lean or tilt when the operator turns to the right or left, as when turning a corner, changing lanes on a highway, or simply following the curvature of a road. Motorcycles generally have rear view mirrors mounted on them to enable the operator to monitor traffic and road conditions behind him. During turns the motorcycle mirrors tilt with the frame of the motorcycle, with the result that one mirror is raised to an elevated position with respect to its position during straight riding while the other mirror is lowered. On some motorcycles, the mirrors are mounted on a wind fairing that is fixedly connected to the motorcycle frame. However, on other motorcycles the mirrors are mounted on the handlebars, with the result that when the front fork-handlebar assembly is turned to cause the motorcycle to turn, the mirrors are also turned with respect to the frame of the motorcycle.
Motorcycle operators often experience difficulty in detecting vehicles behind them, for example vehicles approaching the motorcycle from either the left rear or right rear. This problem is exacerbated as the motorcycle tilts during a turn. Due to the tilting the motorcycle operator has a significantly diminished view behind him. If the turn is great, with a high degree of tilting and/or turning, the operator cannot utilize conventionally mounted mirrors to see behind him, but instead must either turn his head or look beneath his arm on the side toward which his vehicle is tilting. Either of these maneuvers by the operator is difficult to execute while wearing a helmet. Moreover, both are unsafe, as they require a prolonged time without viewing the road ahead, as compared with a quick glance at the rear view mirrors. This situation is even worse when the mirrors are mounted on the motorcycle handlebars and so turn with respect to the motorcycle frame as the operator turns the front wheel of the motorcycle.
Adjustable mirror mounts are known for other vehicles. For example, U.S. Pat. No. 3,469,901 discloses an electrical system for automatically angularly adjusting the mirrors on the cab of a tractor trailer. A series of spaced electrical contacts is arranged on the fifth wheel of the tractor, while the kingpin plate of the trailer carries a conducting bar adapted to engage the contacts as the tractor turns with respect to the trailer. Contact between the various electrical contacts and the conductor bar causes activation of an electromagnetic device for pivoting or turning the rear view mirrors to provide the operator with an appropriate rear view both during straight driving and during turning.
U.S. Pat. No. 3,749,480 discloses another automatic tractor-trailer mirror rotation system, including a relative rotation sensor, an electronic signal generator, a motor, and control circuitry for coupling the motor to the signal generator and for providing a feedback signal to the signal generator. The system rotates either the right or the left rear view mirror relative to the right or left rear wheel as the tractor turns relative to the trailer. The system is said to be very simple to install without requiring substantial modification to the vehicle.
Other self-aligning rear view mirror systems are disclosed in, for example, U.S. Pat. Nos. 3,199,075; 3,383,154; and 3,640,609. U.S. Pat. No. 3,199,075 discloses a system which moves the mirror between predetermined positions in response to operation of the right or left turn signal indicator. U.S. Pat. No. 3,383,154 shows a mechanical arrangement, utilizing a weight, for moving the mirror according to a particular ratio between the arcuate motion of the weight and the arcuate motion of the mirror. U.S. Pat. No. 3,640,609 discloses a hydraulic system responsive to the rotation of a shaft in the vehicle steering column for controlling the mirror position.